transfer exchagne server 2007 roles

Hi,

Due to performance issue, I create the new exchange server 2007 (ent) on window server 2008 (ent) and transfer all the mailboxes from old server to new server and also regenrateand configure the SSL UCC certificate
After 2-3 days I switch off the old exchange , now I need to create some account for our branch office and they will use outlook anywhere (RPC over HTTP) based account. Brach office users also not a part of domain users. My problem is that when I try to configure the branch office user system outlook user rpc over rpc, the outlook not make connection with server, I try to find the solution for 3 days, but finally I start the my old exchange server also than configure the the remote users with this server. And its workign fine.
Now I want to transfer the all roles from old exchange server to new exchange server but also dont want to uninstall the old exchange server also, pls suggest..

"The solutions and answers provided on Experts Exchange have been extremely helpful to me over the last few years. I wear a lot of hats - Developer, Database Administrator, Help Desk, etc., so I know a lot of things but not a lot about one thing. Experts Exchange gives me answers from people who do know a lot about one thing, in a easy to use platform." -Todd S.